The demand for solid-surface countertops such as granite, marble, engineered stone, and Corian® has steadily risen over the past decade. As the demand for solid-surface countertops, vanities, tub decks, fireplace mantles and hearths continues to grow, it becomes more imperative for solid-surface fabrication companies to work faster, without sacrificing quality, in order to meet this demand.
In working with solid surfaces, it is often desirable to join two or more pieces of material together. For example, in U.S. Pat. No. D644497 issued on Sep. 6, 2011, a solid-surface seaming apparatus is claimed. FIG. 1A is a drawing from the '497 patent, and the seam-setter apparatus 10 uses two suction cups 15, 25, which are operated by hand pumps 20, 30. The user of this apparatus lays down two pieces of a solid-surface material, and at the edge of each piece applies adhesive. The goal is to bring both pieces together to form a stable, strong and level seam. To do this, the user places the first suction cup 15 on one piece of a solid-surface material and the second suction cup 25 on the second piece of solid-surface material, and then the user activates both hand pumps 20, 30. It should be noted that some seam setters have an automated pump, in which case the user would activate the pump to draw a vacuum in the suction cups 15, 25. Once the vacuum is drawn, the user turns the knob 35, mounted on a threaded rod 37, which draws the suction cups 15, 25 linearly closer to each other, thereby closing the seam between the two pieces of the solid-surface material. Then the user turns the leveling knobs (38a, 38b) that are mounted to threaded rods, which push down near the seam until both solid-surface pieces are at the same level. The seam-setter apparatus 10 is left on the two pieces of the solid-surface material until the adhesive cures.
Suction cups are used to strengthen and carry fragile material. As in the example shown in FIG. 1B, multiple suction cups are connected to a longer frame or rigid beam that keeps fragile material from flexing and/or breaking during transport and general handling. In other examples, the suction cup may be connected to a crane-type apparatus, such that suction can be drawn on the cups and the operator can activate the crane to lift and position the material. As another example, the suction cup may be connected to a handle as shown in FIG. 1C or as shown in U.S. Pat. No. 3,240,525 issued to Wood on Dec. 13, 1963, incorporated herein by reference; such an apparatus allows the user the move the material into more precise placement.
FIG. 2, which is a new design by the same inventor of the present invention, illustrates a suction cup 40 removed from the device. The cup has a port 45 formed into the pliable suction surface 50, wherein the port 45 is connected to the pump, such that the cup can form a vacuum upon activation of the pump.
Because suction cups are often used in dirty environments that are constantly polluted by polishing and grinding, it is important to cover the cups to prevent damage to the pliable surface 50 and the sealing edge 52 of the suction cup. Such damage can render the suction cup inoperable by causing air leaks that prevent a proper vacuum from forming. This in turn can cause the suction cup to fail while in use, damaging the material, or worse, injuring the user. The cover currently used for suction cups is shown in FIG. 3. The suction cup 40 is shown connected to a larger apparatus 55 (which may be a seam setter, a stiffening device, a crane, etc.). A cover 60 covers the pliable surface 50 and the sealing edge 52 of the suction cup 40. This cover 60 snaps over the edge of the suction cup 40 and requires the user to bend the rigid plastic tab 65. This is shown in FIGS. 4 and 5. Once the hard plastic tab 65 is bent, the suction cup 40 can be slipped under the tab 65, as shown in FIGS. 6 and 7. Because the previous cup covers 60 have been made from rigid plastics, they require holes 70 in the bottom (see FIG. 7) in order for the two halves of the injection mold to create the top lip edge that snaps over the rubber edge. Also, the cover 60 has a gap 72 around the edge of the suction cup.
Unfortunately, the prior art design has several problems. First, the hole 70 in the bottom does not protect the sealing edge 52 at that spot as shown in FIG. 8, allowing dust and debris to enter and damage the suction cup. The hole 70 can also damage the sealing edge 52 if the rigid plastic cover 60 and/or tab 65 has a sharp edge. Also, the hole 70 can deform the sealing edge 52 if the sealing edge rests on the hole 70 with any weight; such a deformation could cause tool failure. The hard plastic tab 65 eventually breaks from bending it to get the cover 60 on the cup, as shown in FIG. 9 where the plastic has plastically deformed and shows discoloration (at position 66) from stress. Having to bend the hard plastic tab 65 is not easy (it takes time and effort), and if the hard plastic tab 65 is molded thinner to make this easier, then it will have a greater tendency to break. Also, many vacuum cups have a vacuum release “nub” 75 that juts away from the vacuum cup (see FIG. 10). This nub 75 is often in the way when trying to attach the cover 60, such that the cover 60 needs to be “clocked” in the proper orientation before putting it on, again wasting time. The gap 72 also allows for dust, debris and grime to enter into/onto the suction cup, which degrades the suction cup material and lowers the life expectancy of the suction cup.
What is therefore needed is a suction cup cover that overcomes these deficiencies and provides full protection of the sealing edge of the suction cup.